What article should be used in such sentences?
What article should be used in the following sentence?
He was English by [a/the/] blood.
I feel there should be a zero article here, but I was taught that the zero article is impossible in English.
Solution 1:
He was English by blood is correct.
It isn't true that the zero article is impossible in English. It all depends on the sentence.
Solution 2:
No article is required here because it's a fixed expression indicating family relationship by birth rather than marriage. Example: They are related by blood. My explanation is based on CALD3.